Container and method relating to telescopically expanded diaphragms



ARR 3,275,193

Sept. 27, 1966 1, R B

CONTAINER AND METHOD RELATING TO TELESCOPICALLY EXPANDED DIAPHRAGMS 2Sheets-Sheet 1 Original Filed March 15. 1962 FIG. 2

6| 60 IRWIN R. BARR INVENTOR Sept. 27, 1966 l. R. BARR 3,275,193CONTAINER AND METHOD RELATING TO TELESCOPICALLY EXPANDED DIAPHRAGMSOriginal Filed March 15, 1962 2 Sheets-Sheet 2 IRWIN R. BARR i EINVENTOR l2" \1 l '1 ll '& ATTORNEY United States Patent 3,275,193CONTAINER AND METHDD RELATING TO TELE- SCOPICALLY EXPANDED DIAPHRAGMSIrwin R. Barr, Baltimore, Md., assignor to Aircraft Armaments, Inc.,Cockeysville, Md., a corporation of Maryland Continuation of applicationSer. No. 179,970, Mar. 15, 1962. This application Dec. 21, 1964, Ser.No. 423,631

11 Claims. (Cl. 2221) This application is a continuation of copendingapplication Serial Number 179,970, filed March 15,1962, whichapplication is now abandoned.

This invention relates to containers, and more particularly todispensers and expansible chamber containers.

Briefly, according to one broad aspect of the invention, there isprovided a propellant-gas sealed material propelling arrangementincluding a case with a bore formed therein and a folded cup-shaped Wallor diaphragm seal formed of malleable material capable of cold flow to asubstantially permanent plastic deformation, in which the cup-shapedseal has a longitudinally extending inner tubular body portion closed atone end and open at its other end, with a transversely outfolded endportion integral with and formed at the open end with means connectingthe outfolded end portion to the casing in substantially gas pressuresealing relation, gas pressure generating means adjacent the closed endof the cup-shaped seal for imparting longitudinal inside-out telescopicreversal movement of the tubular body portion toward and through theopposite open end, and the invertible cupshaped diaphragm seal beingformed with a plurality of annular undulating folds having annular foldportions of greater diameter than other annular folded portions thereof,this providing among other advantages increased strength against lateralcollapse of the cup-shaped seal during material propulsion anddischarge, and in several different embodiments a desired increase indiaphragm extension, over that without such annular folds, when thedevice is operated. In operation, the smoothly undulating annular foldsserve to prevent lateral collapse of the cup-shaped seal, which collapsewould materially decrease the utility of the apparatus in that asubstantial quantity of the material to be discharged would becomeentrapped. In the process of discharging the material, the cup-shapedseal is rolled inside-out through its open end by the action of thepropellant gas on the closed opposite end, which effectively moves thecup-shaped seal in the manner of a hollow self-extensible piston, theinner material carrying cavity of which becomes smaller and smaller asthe piston body progressively turns inside-out and moves forward, andthe actuating chamber becoming correspondingly larger than its originalrelatively small interior and exterior size and volume. During thismovement of the cup-shaped seal there is a substantial tendency for thelateral side walls to be laterally crushed inwardly, and the variousembodiments of the present invention are effective to prevent thisoccurence. Inasmuch as the cupseal is formed of malleable material (asdistinguished from highly elastic material such as rubber or the like)capable of cold flow to a substantially permanent plastic deformation inorder to further aid in conjunction with the annular undulating folds toprovide adequate strength against lateral collapse, in order to minimizethe possibility of blowout of the cup-seal after inside-out telescopicreversal movement through its open end, it is desirable to provide acasing extension or other restricting annular wall beyond the open endof the cup-seal, with an interior casing wall having an internaldiameter at various positions along its length which is greater than allof the annular folded portions, but which is only sufficiently greaterrelative to the respective portion of the seal which will 3,275,193Patented Sept. 27, 1966 be engaged therewith after inside-out movementby a difference in diameter within the elastic elongation limit of themalleable seal material.

According to a further broad aspect of the invention, in carrying outthe formation of the foregoing described material-propelling arrangementthere is also provided a novel telescopically expandable housing formingan expandable chamber and including a telescopically expandable foldedtubular body portion formed of malleable material, such as aluminum,steel, nickel, etc., capable of cold flow to a substantially permanentplastic deformation, the folded tubular body portion being formed of aplurality of annular smoothly undulating folds spaced along its lengthand being axially extendible telescopically within itself. According toone preferred embodiment the telescopically expandable folded tubularbody portion has a plurality of interfolded interfacing longitudinallyextending tubular portions disposed radially one within the other, theinnermost tubular portion having a closed end facing an opposite closedend of a further body portion of the housing and defining therewith atelescopically expandable cavity or chamber. In addition to theadvantage of improved strength for this inside-out telescopic unrollingbody portion, various configurations employing such annular smoothlyundulating folds enable substantially increased lengthwise expansion ofthe folded tubular body portion from a given original folded length withconsequent increase in the expanded chamber.

A unique expansion chamber and method of expanding an enclosed chamberfrom one size to a larger size is thus alforded according to invention,and in the illustrated embodiment this expansion chamber and method areem ployed in the construction and operation of several uniquedispensers.

Still other objects, features and attendant advantages will becomeapparent to those skilled in the art from a reading of the followingdetailed description of several physical embodiments constructed inaccordance therewith, taken in conjunction with the accompanyingdrawings wherein:

FIGURE 1 is a longitudinal cross-sectional view of a container having astraight single tubular walled diaphragm shown in its position occupiedprior to the dispensing operation.

FIGURE 2 is similar to FIGURE 1 except that the diaphragm is shown inits position occupied subsequent to the dispensing of an initialquantity of material.

FIGURE 3 is similar to FIGURE 1 except that other diaphragm positionsare shown corresponding to the dispensing of larger quantities ofmaterial.

FIGURE 4 is a fragmentary longitudinal section view of a dispensershowing one embodiment of the connection between the shells making upthe container and the diaphragm inside the container.

FIGURES 5 and 6 are longitudinal cross-sectional and schematic views ofone embodiment showing an undulated diaphragm according to the inventionin its position prior to dispensing and at several positions duringdispensing.

FIGURES 7 and 8 are longitudinal cross-section views of still anotherand preferred embodiment showing a diaphragm resistant to crushing andits position prior to dispensing and after initial dispensing.

FIGURE 9 is a longitudinal cross-section view of a further embodimentshown prior to and during dispensing.

Referring now to FIGUE 1, there is shown a dispenser 10 which includeshollow container 11, diaphragm 12 and valve means 13.

Container 11 comprises upper shell 14 and lower shell 15. These shellsmay be of pressure weldable material such as aluminum, etc., althoughother materials are satisfactory. Upper shell 14 has tubular walls 16and top wall 3 17 that closes one axial end of the shell. The other endof shell 14 is open, and at, the open end, walls 16 are pro vided with acircumferential outturned lip or flange 18. Top wall 17 has anupstanding circular flange 19 centered thereonsurrounding opening 20into which valve means 13 is inserted. 1

Bottom shell 15 has tubular walls 21 and bottom wall 22 that closes oneaxial end of the shell. The other end of shell 15 is open, and at theopen end, walls 21 are provided with a circumferential outturned lip orflange 23.

Diaphragm or expandable wall 12 has three main parts: tubular portion24, lip or flange portion 25 and closure 26. Portion 24 is slightlysmaller in diameter than lower shell 15 and is about as long as shell15. It has circumferential outturned flange 25 at one axial end andclosure 26 at the other axial end. Diaphragm or expandable wall 12 isformed of a malleable material capable of cold flow incremental rollingbending movement to a substantially permanent plastic deformation, suchas aluminum, steel, nickel, etc.

Valve means 13 includes 'base 26, body 27 and control 28. Base 26 isprovided with circumferential groove 29 into which radial lip 30 onflange 19 is engaged to securely attach the valve means to thecontainer. Curved orifice '31 in body 27 interconnects with hole 32 inbase 26 for defining a passageway that vents the interior of shell 14.Control 28 extends axially through base 26 and body 27 and 'seatsagainst a conical rim defining a portion of hole 32. Spring means (notshown) may be used to maintain control 28 seated against the rim. Thiscontrol is manually operable to permit the container to be vented.

The assembly of the container and diaphragm may be understood byreferring to FIGURE 4. Diaphragm 12 is first positioned in lower shell15 with lip 25 engaged over lip 23 so that tubular portion 24 isconcentric with the shell and closure 26 is adjacent to bottom wall 22.Next, shell 14 is placed on the configuration so that shell 14 opensinto shell 15 with lip 18 engaged =over lip 25 of the diaphragm. The lipconfiguration appears as in FIGURE 4, and if the material of the shellsand diaphragm are pressure weldable, the lips may now be pressure weldedas at 33 to form a mechanical connection between the shells and ahermetic seal which permits the diaphragm to divide the interior of thecontainer into two compartments. If the material is not pressureweldable, other conventional joints can be used. Gas compartment 34 isgenerally annular in shape and is defined by surface 35 of the diaphragmand the inside of walls 24 and 22. Material compartment 36 is generallycylindrical in shape and is defined by the other surface 37 of thediaphragm and the inside of walls 16 and 17.

After compartment 36 is filled with dispensible material, valve means 13may be securely attached. In this manner, compartment 36 is closed andmay be vented by selective operation of control 28 of the valve means.Propellant material may now be introduced into chamber 34 through anaperture (not shown) in wall 22. After such material is introduced,chamber 34 is sealed by closing the aperture. The material is preferablyintroduced into the gas chamber in liquid form. The particular materialchosen will depend upon the ambient temperature of the environment inwhich the dispenser is to be used. In general, the liquid will evaporateuntil the pressure in the gas chamber at the desired operatingtemperature of the dispenser is around 50 to 75 p.s.i.g. Since thevolume is relatively small when the diaphragm is in this condition, mostof the material remains in the liquid phase.

When the valve means is selectively operated to vent chamber 36, thepressure in chamber 34 acts to deform the diaphragm in a particularmanner. This can best be understood by recognizing that the area ofclosure 26 exposed to the gases is much larger than the area of lip 25exposed to the gases. As a result, the force exerted on closure 26 anddirected away from wall 22 exceeds the force exerted on lip 25 anddirected away from wall 22. When the valve means is operated, closure 26is thrust upwardly away from wall 22 causing lip 25 to be deformed intoa tube having the same diameter as shell 14 and engaged with walls 16. Apart of the tubular portion of the diaphragm is deformed into acircumferential lip that connects the newly formed tube with theremainder of the tubular portion. In other words, the gas pressurecauses the diaphragm to be rolled up into the upper shell when the valvemeans is selectively operated. This causes gas chamber 34 to expand tothe volume indicated at 34' in FIGURE 2 while chamber 36 decreases tothe volume indicated at 36 in FIGURE 2. The change in volume of thechambers equals the volume of material dispensed.

Upon further operation of the valve means, the diaphragm may move to theposition shown in FIGURE 3 where the new gas chamber 34" is larger than34 and the new material chamber 36" is smaller than 36. It should benoted that tubular portion 24 of the diaphragm is bent and expandedduring deformation from its original condition in FIGURE 1 to itssubsequent conditions in FIG- URES 2 and 3, and that once a portion ofthe diaphragm engages the walls 16 of the upper shell, no furtherrelative motion between such portion and the walls occurs. In otherwords, the deformation of the diaphragm is such that there is nofrictional resistance to its deformation. This operates to limit thework required to be done by the gas to the bending and stretching of thediaphragm, and the movement of the dispensed volume of material throughthe valve means, without Wasting work in frictional engagement of thediaphragm with the container casing or shell 14.

As the volume of chamber 34 expands, more liquid material thereinevaporates to maintain the pressure at the desired operating level. Atthe end of the operation, the diaphragm is completely unrolled intoupper shell 14, substantially all of the material having been forcedfrom the container and all of the propellant gases being retained in theenlarged container chamber.

To streamline the construction, lips 18, 23, and 25 may be bent overinto engagement with the shells as suggested by the arrows of FIGURE 4and as shown in FIG- URES 1-3.

Where the viscosity of the material to be dispensed is low, the pressurein the material compartment is essentially atmospheric pressure when thevalve means is operated. Because the diaphragm is necessarily thin whenthe invention is employed in dispensers such as for foodstuffs asillustrated, there is a tendency for the tubular portion to be crushed.Where the work required to crush the tubular portion is less than thework required to unroll the diaphragm, operation of the valve means isaccompanied by radial collapse :of the diaphragm instead of axialdisplacement of the closure. For this and other reasons the device ofFIGURES 1-3 is not preferred, although it does' have limited utility insome instances, as where large ratios of expanded length versuspre-expanded length are not advantageous, or where radial crushresistance can be relatively small.

To obtain improved total lateral crush resistance as well as providing alarger ratio of expanded length/preexpanded length of the pressureexpanded chamber it is highly desirable to provide a plurality ofannular folds or undulations along the length of the telescopicallyinvertible diaphragm body portion. To this end, in the improvedarrangement of FIGURE 5 a series of circumferential ridges 40 is formedin the diaphragm 12. The undulated tubular portion 41 of diaphragm 12resists the radial inwardly directed forces acting on portion 41 due tothe gas pressure. This arrangement only slightly increases the totalwork required to unroll the diaphragm, but effectively will prevent itscollapse. It is, of course, necessary that the amplitude of theundulations formed by the ridges 40 be small enough that the diaphragmmaterial will not be stretched beyond its plastic flow limit when rolledinside-out, in order to prevent breakage of the diaphragm during theoperation of the device. Various positions of diaphragm 12' during thedispensing operation are shown in FIGURE 6.

One advantage of the dispenser lies in the fact that shells 14 and aresubstantially identical. That is, each may be made by an impactextrusion or deep draw process, and each has a wall length that is thesame. Thus, each shell need be only one half the height of the completeddispenser, and can be easily formed on conventional equipment to producedispensers of the normal size. The fact that each shell is half thedispenser height is utilized in the diaphragm design because the jointthat mechanically connects the shells into a unitary container alsoprovides the attachment and sealing means for the diaphragm which, inthe design shown in FIGURES 1-6, must extend at least half the height ofthe container.

A highly advantageous and preferred modification is shown schematicallyin FIGURES 7 and 8 at 10 employing a modified multiple fold diaphragmseal .12 which may be unrolled and extended to a length several timesgreater than its initial folded length. The attachment of the shells orcasing sections 14, '15 and diaphragm 12" may be the same as previouslydescribed. Diaphragm 12 is multiple-folded in a series of substantiallyconcentric tubular folds, having a first tubular portion 50 that extendsfrom the out-turned lip 51 attaching the diaphragm to the containercasing or shell, toward bottom wall 52 of bottom shell 15. Tubularportion 50 connects through a smooth annular bend 53 adjacent to bottom52 with a second concentric tubular portion 54 which in turn connectsthrough a further smooth annular bend 55 with a third innermost tubularportion 56 extending from told 55 toward bottom 52 and terminating in anintegral end closure wall 57 which is adjacent to bottom 52. Tubularfolded portions 50, 54 and 56 vfit in substantially concentric relationwithin the base end section 15 of the shell or casing.

In operation, diaphragm 12" is axially telescopically unrolled andextended within itself through incremental rolling and radial stretchingof the material sequentially through the axially moving annular folds bythe gas pressure acting thereon, with the inner tubular folded portions50, 54 and 56 beingtelescoped axially outwardly as an integral unittoward the material discharge end of the casing 14', which may be ofrequisite extended length to accommodate the axially extended diaphragm12". An intermediate position of the diaphragm 12" is indicatedschematically in broken lines in FIGURE 8.

Another modification of the diaphragm and container is shown in FIGURE9. Diaphragm 12 is similar to diaphragm 1 2' in that both are extremelyresistant to radial deformation due to the gas pressure. As shown inFIGURE 9, diaphragm 12 has a generally cylindrical tubular portion 60that is formed of a series of stepped cylinders 61 interconnected bycircumferential shoulders 62. The width of the shoulders may vary fromthree times the metal thickness of the diaphragm to ten times thethickness, although this range is not critical. Such width reinforcesthe tubular portion against radial collapse due to the (gas pressure ingas compartment 63. Circumferential lip 64 at the open end of diaphragm12" is interposed between outturned flanges 65, 66, on the containerhalves. Where design considerations require shoulders 62 to have sizablewidths, top 67 of the container may be provided with a series of steps68 which match the contour of diaphragm 12. In this manner, thecontainer may be completely emptied, because the top of the containermatches the inverted shape of the diaphragm. It should be noted that theoperation of the embodiment of FIGURE 9, so far as the engagement of thediaphragm with the wall is concerned, is the same as the previouslydescribed embodiments. Once the diaphragm contacts the walls of thecontainer, there is no relative motion, thereby eliminating wastedfunctional drag on the diaphragm.

While the invention has been described with respect to several physicalembodiments and modes of practice thereof, it will be understood bythose skilled in the art that various modifications and improvements maybe made without departing from the scope and spirit of the invention.Accordingly, it is to be understood that the invention is not to belimited by the particular illustrative embodiments, but only by thescope of the appended claims.

That which is claimed is:

1. The method of forming a larger enclosed chamber from a smallerenclosed chamber defined by a telescopically expandable folded tubularbody portion closed at one end and a further fiuid-tight-interc-onnectedbody portion having an open end and an opposite closed end facing theclosed end of said telescopically expandable body portion, said foldedtubular body portion being formed of material capable of cold flow to asubstantially permanent de-formtion and having a plurality of annularsmoothly undulating folds disposed along its length and between saidclosed end and said open end of said further interconnected bodyportion, comprising exerting a longitudinally expanding pressure on saidone closed end of said folded tubular body portion in a directionlongitudinally away from said closed end and toward said open end ofsaid further interconnected body portion and along the direction ofpotential telescopic expansion thereof through said open end, andtelescopically longitudinally moving said closed end and the connectingundulating folded side wall material of said folded tubular body portionfrom within itself and away from said opposite closed end and throughsaid open end, and sequentially plastically deforming said undulatingfolds through an inside-out incremental rolling reverse bend andradially stretching and expanding the material of the inner folds beyondits elastic elongation limit but Within the elongation-torupture limitupon passing of said inner folds through said reverse bend, all of saidsteps being effected as a function of differential pressure on said oneclosed end of said folded tubular body portion to thereby turn saidtubular body portion inside out and expand said chamber.

2. A propellant-gas-sealed material-propelling arrange. ment comprisingcasing means having a bore formed therein; a cup-shaped diaphragm sealformed of malleable material of substantially constant thickness andinternal rigidity, capable of cold flow to a substantially permanentplastic deformation and having a longitudinally extending inner tubularportion closed at one end and conmeeting at the opposite end with theremaining body portion, said inner tubular portion extending lengthwisealong a portion of the length of said bore, a transversely outfolded endportion integral with and formed at the opposite open end of saidtubular body portion, and means connecting said outfolded end portion tosaid casing in substantially gas pressure sealing relation, gas pressuregenerating means adjacent said one closed end of said cupshapeddiaphragm seal for imparting longitudinal insideout telescopic reversalmovement of said tubular body portion toward and through said oppositeopen end, said cup-shaped diaphragm .sea'l being formed with a pluralityof annular smoothly undulating folds and having annular folded portionsof greater diameter than other annular folded portions thereof, theannular wall of said casing means extending longitudinally from andbeyond said opposite open end in a direction away from said closed oneend of said cup-shaped seal and being of greater diameter than all ofsaid annular folded portions, the ratio of the diiference between therespective internal diameter of each of said other annularly foldedportions and the respective associated internal diameter of said casingmeans at the inside-out extending position of said cup-shaped sealrelative to the original internal diameter of said other folded portionsbeing greater than the elastic elongation limit of the seal material andless than the elongation limit to rupture of the seal material, wherebythe seal may be outrolled inside-out through its said opposite open endto an enlarged position with its original inner wall permanentlyplastically radially expanded to form the inverted outer wall of saidseal in substantial contact with the respective associated effectiveinner wall portion of said casing means.

3. A pr-opellant-gassealed propelling arrangement according to claim 2,said annular folded portions forming a plurality of integrallyinterconnected mutually laterally interfacing tubular-portions spacedradially one within the other and including said first mentioned tubularbody portion as the radially innermost tubular portion, said meansconnecting said transversely outfolded end portion to said casing meansincluding said annularly folded portions other than said first-mentionedtubular body portion.

4. A propellant-g-as-sealed propelling arrangement according to claim 3wherein said plurality of tubular portions have substantiallycylindrical mutually interfacing spaced apart wall portions respectivelyinterconnected by successively longitudinally opposite smoothreverse-curved annular end wall portions.

'5. A propellant-gas-sealed propelling arrangement according to claim 3further comprising a manually operable material-discharge control devicedisposed on said casing [means opposite said closed one end of saidseal.

6. A pr-opellant-gas-sealed propelling arrangement according to claim 2wherein said longitudinally extending tubular body portion has saidsmoothly undulating folds successively longitudinally spaced inalternating increasing and decreasing diameter form along its length.

7. A propellant-gas-sealed propelling arrangement according to claim 6wherein said successively longitudinally spaced smoothly undulatingfolds are of substantially repetitive maximum and minimum diametervalues.

8. A propellant-gas-sealed propelling arrangement according to claim 2,said annularly folded portions forming a plurality of integrallyinterconnected stepped tubular cylindrical portions of successivelyincreasing diameter along said first-mentioned tubular body portionprogressing longitudinally from said closed one end, said successivelyincreasing diameter tubular cylindrical portions being successivelyfurther spaced from said closed one end of said inner tubular portion,and said casing means being formed longitudinally beyond saidtransversely outfolded end portion with succeeding decreasing diameterstepped tubular cylindrical inner wall surfaces decreasing in diameterby steps longitudinally corresponding to the respective opposite stepsin said stepped tubular body portion of said seal.

9. A propellant-gas-sealed material-propelling arrangement comprisingcasing means having a bore formed therein; a cup-shaped diaphragm sealformed of malleable material of substantially constant thickness andinternal rigidity, capable of cold-flow to a substantially permanentplastic deformation and having a longtiudinally extending inner tubularportion closed at one end and connecting adjacent its other open end ina smooth circumferential bend with the remaining body portion, whichsaid remaining body portion is in connection adjacent its 8 other openend in fluid sealing relation to said casing, said inner tubular portionextending lengthwise along a portion of the length of said bore,gas-pressure-generating means adjacent said one close-d end of saidcup-shaped diaphragm seal for imparting longitudinal inside-outtelescopic reversal movement of said tubular body portion throughitself, said cup-shaped diaphragm seal being formed with a plurality ofannular smoothly undulating folds and having annular folded portions ofgreater diameter than other annular folded portions thereof, the annularwall of said casing means extending longitudinally from and beyond saidseal in a direction away from said gas-pressure-generating means and ina direction along the line of motion of said seal during its saidinsideout telescopic reversal movement under the influence of said gaspressure, said longitudinally extended wall of said casing means beingof greater diameter than a plurality of said annular folded portions,the ratio of the difference between the respective internal diameter ofeach of said other annularly folded portions and the respectiveassociated internal diameter of said casing means at the inside-outextended position of said cup-shaped seal relative to the originalinternal diameter of said other folded portions being greater than theelastic elongation limit of the seal material and less than theelongation-to-rupture limit of the seal material, whereby the seal maybe out- ,rolled inside-out through its said opposite open end to anenlarged position with its original inner wall permanently plasticallyradially expanded to form the inverted outer wall of said seal insubstantial contact with the respective associated effective inner Wallportion of said casing means.

10. A propellant-gas-sealed propelling arrangement according to claim 9,said annular folded portions forming a plurality of integrallyinterconnected mutually laterally interfacing tubular portions spacedradially one within the other and including said first mentioned tubularbody portion as the radially innermost tubular portion, said meansconnecting said transversely outf-olded end portion to said casing meansincluding said annularly folded portions other than said first-mentionedtubular body portion.

11. A propellant-gas-sealed propelling arrangement according to claim10, wherein said plurality of tubular portions have substaniallycylindrical mutually interfacing spaced apart wall portions respectivelyinterconnected by successively longitudinally opposite smoothreverse-curved annular end Wall portions.

References Cited by the Examiner UNITED STATES PATENTS 1,099,855 6/1914Mallory 92l03 X 2,343,320 3/1944 Parker l3830 2,953,304 9/1960 Sellinger222-386.5 X 3,104,526 9/1963 Hirschfeld et al. 222-386.5 X

ROBERT B. REEVES, Primary Examiner.

LOUIS I. DEMBO, Examiner. S. H. TOLLBERG, Assistant Examiner.

1. THE METHOD OF FORMING A LARGER ENCLOSED CHAMBER, FROM A SMALLERENCLOSED CHAMBER DEFINED BY A TELESCOPICALLY EXPANDABLE FOLDED TUBULARBODY PORTION CLOSED AT ONE END AND A FURTHER FLUID-TIGHT-INTERCONNECTEDBODY PORTION HAVING AN OPEN END AND AN OPPOSITE CLOSED END FACING THECLOSED END OF SAID TELESCOPICALLY EXPANDABLE BODY PORTION, SAID FOLDEDTUBULAR BODY PORTION BEING FORMED OF MATERIAL CAPABLE OF COLD FLOW TO ASUBSTANTIALLY PERMANENT DEFORMATION AND HAVING A PLURALITY OF ANNULARSMOOTHLY UNDULATING FOLDS DISPOSED ALONG ITS LENGTH AND BETWEEN SAIDCLOSED END AND SAID OPEN END OF SAID FURTHER INTERCONNECTED BODYPORTION, COMPRISING EXERTING A LONGITUDINALLY EXPANDING PRESSURE ON SAIDONE CLOSED END OF SAID FOLDED TUBULAR BODY PORTION IN A DIRECTIONLONGITUDINALLY AWAY FROM SAID CLOSED END AND TOWARD SAID OPEN END OFSAID FURTHER INTERCONNECTED BODY PORTION AND ALONG THE DIRECTION OFPOTENTIAL TELESCOPIC EXPANSION THEREOF THROUGH SAID OPEN END, ANDTELESCOPICALLY LONGITUDINALLY MOVING SAID CLOSED END AND THE CONNECTINGUNDULATING FOLED SIDE WALL MATERIAL OF SAID FOLDED TUBULAR BODY PORTIONFROM WITHIN ITSELF AND AWAY FROM SAID OPPOSITE CLOSED END AND THROUGHSAID OPEN END, AND SEQUENTIALLY PLASTICALLY DEFORMING SAID UNDULATINGFOLDS THROUGH AN INSIDE-OUT INCREMENTAL ROLLING REVERSE BEND ANDRADIALLY STRETCHING AND EXPANDING THE MATERIAL OF THE INNER FOLDS BEYONDITS ELASTIC ELONGATION LIMIT BUT WITHIN THE ELONGATION-TORUPTURE LIMITUPON PASSING OF SAID INNER FOLDS THROUGH SAID REVERSE BEND, ALL OF SAIDSTEPS BEING EFFECTED AS A FUNCTION OF DIFFERENTIAL PRESSURE ON SAID ONECLOSED END OF SAID FOLDED TUBULAR BODY PORTION TO THEREBY TURN SAIDTUBULAR BODY PORTION INSIDE OUT AND EXPAND SAID CHAMBER.